This invention relates to a radioactive tracer material injector for use in injecting radioactive tracer material into fracturing fluids used in oil and gas well hydraulic fracturing operations.
In oil and gas well hydraulic fracturing operations radioactive propping materials are sometimes injected into the fracturing fluid which carries the materials into a fracture formed in an earthen formation. When the radioactive propping materials are present in the formation a variety of information may be determined about the hydraulic fracturing operation, such as fracture location with respect to depth, type of fracture produced, number of fractures produced, estimation of fracture thickness, effectiveness of fracturing method, etc.
In such hydraulic fracturing operations employing the use of radioactive propping materials it is only necessary that a small amount of radioactive propping material be present in the proppant ladden fracturing fluids utilized to hydraulically fracture the earthen formation. Since the tracer proppant material mixed into the fracturing fluid is radioactive in nature, the storage, handling and use of such radioactive propping material is regulated by various governmental agencies and laws. Therefore, it is necessary to be able to inject or mix small amounts of such radioactive propping material into the fracturing fluid during the hydraulic fracturing operation without contaminating either personnel conducting the hydraulic fracturing operation or the area where the equipment is located for performing the hydraulic fracturing operation and to allow easy clean-up of residual radioactive propping material in the injection equipment at the termination of the hydraulic fracturing operation.
One such prior art injection equipment for injecting radioactive propping materials is illustrated in U.S. Pat. No. 4,199,680.